[gpm] flaky movement and buttons when using both stick and

[Alessandro Rubini]

>> -3 just tells gpm it's a 3-button mouse, -p makes the cursor visible
>> while selecting in the console.
> 
> Ok, 3-button mouse worked anyway for me.

It's an old option. ps2 mice can have two or three buttons (but it may
apply to other mice as well).

If you have two buttons, right button is "paste". If you have three, middle
button is "paste". Gpm assumes you have two buttons until the middle button
is pressed; if this happens, it assumes you have three. Unless you force
with -2 or -3.

Clicking both is hairy for 2b people, but behacing differently in text
than in X is hairy for 3b people.  From back when most mice had two
buttons, and a few lucky ones had the third.

/alessandro